Is Australian chardonnay the same as chablis?

Almost certainly not. French chablis must contain chardonnay grapes from the chablis region. US chardonnay must contain 80% chardonnay grapes from anywhere. Any other civilized country's chardonnay usually does contain at least some chardonnay. Any 'chablis' from anywhere else can, and usually does, contain any kind of grape or any fruit juice from anywhere on the planet. Some winemakers now use the Word 'chablis' to mean 'white wine'. Good idea => do your own homework online before spending very much money.